THD (Total Harmonic Distortion) and the Power Factor (pf) in 1-phase and 3-phase Alternating Circuit (AC) input lines have been major problems for many years. The THD of 1-phase and 3-phase systems with Inductor-Capacitor (LC) filters is 120% and 28%, respectively. With capacitor input filters, the THD is considerably higher.
Regulatory authorities continue to increase their specifications. When they learn details of the present embodiments, it is possible they may want to significantly increase their specifications.